Detecting circuit, DRAM, and method for determining a refresh frequency for a delay-locked loop module

Abstract

The present disclosure provides a detecting circuit. The detecting circuit includes a clock module, a clock receiver, a delay-locked loop module, a clock tree module, an off-chip driver, a pad, a phase detector, a voltage-detecting module and a control module. The clock module provides a clock signal to the clock receiver. The clock receiver sends the clock signal to the pad through the delay-locked loop module, the clock tree module and the off-chip driver. The control module is coupled to the voltage-detecting module and the delay-locked loop module. The voltage-detecting module is coupled between the control module and the clock tree module, and is configured to detect a voltage of the clock tree module and to send a voltage comparison information to the control module. The control module is configured to control a refresh frequency of the delay-locked loop module.

What is claimed is: 
     
       1. A detecting circuit, comprising:
 a delay-locked loop module configured to maintain a timing relationship between a clock signal and a reference signal; 
 a clock tree module coupled to the delay-locked loop module; and 
 a voltage-detecting module coupled between the delay-locked loop module and the clock tree module and configured to detect a voltage difference between the clock tree module and a reference voltage. 
 
     
     
       2. The detecting circuit of  claim 1 , wherein the voltage-detecting module includes a voltage comparator coupled between the delay-locked loop module and the clock tree module and configured to compare a voltage of the clock tree module with the reference voltage. 
     
     
       3. The detecting circuit of  claim 1 , further comprising a control module coupled to the voltage-detecting module and the delay-locked loop module, wherein the control module is configured to control a refresh frequency of the delay-locked loop module based on a voltage comparison information from the voltage-detecting module. 
     
     
       4. The detecting circuit of  claim 1 , further comprising a phase detector coupled between the delay-locked loop module and the clock tree module, wherein the phase detector is configured to detect a phase difference between the clock signal and the reference signal. 
     
     
       5. The detecting circuit of  claim 4 , wherein the phase detector includes a phase comparator coupled between the delay-locked loop module and the clock tree module, and the phase comparator is configured to compare a phase of the clock signal with the reference signal. 
     
     
       6. The detecting circuit of  claim 5 , wherein when the delay-locked loop module operates at a low frequency, the delay-locked loop module is enabled to adjust the phase of the clock signal after receiving a preset quantity of continuous phase delays or continuous phase advances from the phase comparator. 
     
     
       7. The detecting circuit of  claim 5 , wherein when the delay-locked loop module operates at a high frequency, the delay-locked loop module is enabled to adjust the phase of the clock signal after receiving a phase delay or a phase advance. 
     
     
       8. A DRAM, comprising:
 a memory array; 
 a plurality of sensing amplifiers coupled to the memory array; 
 an I/O buffer coupled to the sensing amplifiers; and 
 a clock generator coupled to the sensing amplifiers and the I/O buffer, wherein the clock generator comprises:
 a delay-locked loop module configured to maintain a timing relationship between a clock signal and a reference signal; 
 a clock tree module coupled to the delay-locked loop module; and 
 a voltage-detecting module coupled between the delay-locked loop module and the clock tree module and configured to detect a voltage difference between the clock tree module and a reference voltage. 
 
 
     
     
       9. The DRAM of  claim 8 , wherein the voltage-detecting module includes a voltage comparator coupled between the delay-locked loop module and the clock tree module and configured to compare a voltage of the clock tree module with the reference voltage. 
     
     
       10. The DRAM of  claim 8  further comprising a control module coupled to the voltage-detecting module and the delay-locked loop module, wherein the control module is configured to control a refresh frequency of the delay-locked loop module based on a voltage comparison information from the voltage-detecting module. 
     
     
       11. The DRAM of  claim 8 , wherein the detecting circuit further includes a phase detector coupled between the delay-locked loop module and the clock tree module, wherein the phase detector is configured to detect a phase difference between the clock signal and the reference signal. 
     
     
       12. The DRAM of  claim 11 , wherein the phase detector includes a phase comparator coupled between the delay-locked loop module and the clock tree module, and the phase comparator is configured to compare a phase of the clock signal with the reference signal. 
     
     
       13. The DRAM of  claim 12 , wherein when the delay-locked loop module operates at a low frequency, the delay-locked loop module is enabled to adjust the phase of the clock signal after receiving a preset quantity of continuous phase delays or continuous phase advances from the phase comparator. 
     
     
       14. The DRAM of  claim 12 , wherein when the delay-locked loop module operates at a high frequency, the delay-locked loop module is enabled to adjust the phase of the clock signal after receiving a phase delay or a phase advance. 
     
     
       15. A method, comprising:
 detecting a voltage of a clock tree module by a voltage-detecting module; 
 comparing the voltage of the clock tree module with a reference voltage; 
 sending a voltage comparison information to a control module; and 
 increasing a refresh frequency of a delay-locked loop module from a preset frequency when the voltage of the clock tree module is decreasing from a high level that is greater than the reference voltage to a low level that is equal to or less than the reference voltage. 
 
     
     
       16. The method of  claim 15 , further comprising:
 maintaining the refresh frequency at a frequency higher than the preset frequency when the voltage of the clock tree module remains at the low level after the refresh frequency is increased. 
 
     
     
       17. The method of  claim 16 , further comprising:
 returning the refresh frequency to the preset frequency when the voltage of the clock tree module is increasing from the low level to the high level. 
 
     
     
       18. The method of  claim 17 , further comprising:
 maintaining the refresh frequency at the preset frequency when the voltage of the clock tree module remains at the high level after the refresh frequency returns to the preset frequency. 
 
     
     
       19. The method of  claim 15 , further comprising:
 enabling the delay-locked loop module to adjust the phase of the clock signal when the delay-locked loop module operates at a low refresh frequency and receives a preset quantity of continuous phase delays or continuous phase advances from the phase comparator. 
 
     
     
       20. The method of  claim 15 , further comprising:
 enabling the delay-locked loop module to adjust the phase of the clock signal when the delay-locked loop module operates at a high frequency and receives a phase delay or a phase advance.